Some people are very well-known. We call them celebrities. These famous people might be rich, play sports, act in movies, or be leaders in government. Sometimes, they are famous because they know other famous people. A long time ago, famous people were different than they are now. A man named Greg Jenner wrote about this. He said famous people have been around for a very long time, even in the early 1700s. Before that, in places like Ancient Greece, sports stars were treated like heroes. In Ancient Rome, actors and fighters called gladiators were also celebrated. There was a man named Thomas Becket who lived 900 years ago. After he died, he became very famous because the church said he was a hero. People shared stories and pictures about him everywhere. So, being famous is not new. It has been happening for many, many years.

In nature, animals and plants change over time. This is called evolution. Scientists like to picture evolution using something called a fitness landscape. Think of it like a map with mountains and valleys. The mountains are the best spots where animals and plants are very successful in having babies. The valleys are not so good. In this map, being close means two living things are a lot alike, and being far means they are different. Moving up the mountain is like getting better at surviving and having more babies. There are high mountains which are the best spots. But there are also smaller hills and deep valleys. If the mountains are many and the valleys are deep, the map is called rugged. But if everything is flat and even, then every place is the same in how good it is for having babies. Animals and plants try to climb to the top of the mountains by changing a little bit over time. They want to reach the highest spot where they can be the best at surviving. Sometimes, it’s hard to find the top, but they keep trying. This idea started with a scientist named Sewall Wright in 1932. Remember, this fitness landscape is just a way to help us understand how living things change and try to get better at surviving and having babies. It is like a game where everyone is trying to reach the top of the mountain.

People love to know what famous people are doing in their lives. This interest in famous people is called "celebrity culture." It is when people watch and buy things that these stars talk about or use. These famous people can be actors, politicians, sports players, or singers. Celebrity culture is just about people wanting to see and know more about stars. It is not about the stars being a group themselves. When many people in a place know about and like these stars, that's when celebrity culture happens. The stars help make it bigger by being part of it. Nowadays, people like to follow what celebrities do every day. They watch where they go, who their friends are, and what they like. This has become normal for many people. They use celebrity culture to have fun and forget about real-life problems for a while. The interest in celebrities started in the United States a long time ago, over 100 years ago. At first, it was mostly rich people who wanted to be famous and were talked about in magazines. But soon, it changed, and all kinds of famous people were interesting to the public.